diane? >> thanks so much, lama. >>> now, we head over to china tonight, where you can see it once again, that smog, back. and again, still beyond the ability to measure exactly how much hazardous material is in what the chinese are breathing. and there was another staggering sight, an infrastructure collapsed in guangzhou. watch. a whole complex of homes swallowed by a massive sink hole, 30 feet wide, triggered by construction on an underground subway station nearby. 300 people were evacuated. no one was injured. >>> and down under now to australia, where this was the strange scene on the beaches there. sea foam billowing up at a level we've not seen before. entire beaches covered in it. spawned by a tropical cyclone that hit last week. the foam, a reminder of the fury of that cyclone. >>> and back here at home, the latest surprises in this season of extreme weather. watch this. it's an ice skating rink in wisconsin. last week, closed, because the arctic air was too cold. but today, it was c